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Physics Exam

The following concerns a question in a physics degree exam at the University of Copenhagen:

"Describe how to determine the height of a skyscraper with a barometer."

One student replied:

"You tie a long piece of string to the neck of the barometer, then lower the barometer from the roof of the skyscraper to the ground. The length of the string plus the length of the barometer will equal the height of the building."

This highly original answer so incensed the examiner that the student was failed. The student appealed on the grounds that his answer was indisputably correct, and the university appointed an independent arbiter to decide the case. The arbiter judged that the answer was indeed correct, but did not display any noticeable knowledge of physics. To resolve the problem it was decided to call the student in and allow him six minutes in which to provide a verbal answer which showed at least a minimal familiarity with the basic principles of physics.

For five minutes the student sat in silence, forehead creased in thought. The arbiter reminded him that time was running out, to which the student replied that he had several extremely relevant answers, but couldn't make up his mind which to use.

On being advised to hurry up the student replied as follows:

"Firstly, you could take the barometer up to the roof of the skyscraper, drop it over the edge, and measure the time it takes to reach the ground. The height of the building can then be worked out from the formula H = 0.5g x t squared. But bad luck on the barometer."

"Or if the sun is shining you could measure the height of the barometer, then set it on end and measure the length of its shadow. Then you measure the length of the skyscraper's shadow, and thereafter it is a simple matter of proportional arithmetic to work out the height of the skyscraper."

"But if you wanted to be highly scientific about it, you could tie a short piece of string to the barometer and swing it like a pendulum, first at ground level and then on the roof of the skyscraper. The height is worked out by the difference in the gravitational restoring force T = 2 pi sqroot (l / g)."

"Or if the skyscraper has an outside emergency staircase, it would be easier to walk up it and mark off the height of the skyscraper in barometer lengths, then add them up."

"If you merely wanted to be boring and orthodox about it, of course, you could use the barometer to measure the air pressure on the roof of the skyscraper and on the ground, and convert the difference in millibars into feet to give the height of the building."

"But since we are constantly being exhorted to exercise independence of mind and apply scientific methods, undoubtedly the best way would be to knock on the janitor's door and say to him 'If you would like a nice new barometer, I will give you this one if you tell me the height of this skyscraper'."

It is told, that the student was Niels Bohr, who later received the Nobel prize for Physics.

Light, one of the very important parts of human living support, has tremendous benefit for us. Light itself is composed of many different rays. One of the components of light, called as blue light, has been known to tamper with our circadian rhythm.

Blue light itself can come from a lot of sources, including the lamp inside your room. However, the source which gives the most impact on people are from electronic devices. In this technology era, it's very hard for us to run away from using electronic devices. Those devices, such as Laptops and Handphones, have tremendously improve our quality of life by making our life easier and more fun through a lot of applications and systems available. Unfortunately, blue light emitted through the screen of those devices can affect our quality of sleep. Some research even advised us not to use our phone a few hours before we are going to sleep to improve our sleep quality.

Just recently, a news spread about a young lady, died due to attack of a Needle fish. The story began when she was having a vacation with her family at Tanjung Karang beach, Makassar, Indonesia. This unfortunate event happened on January 01, 2016.

Liena (39) was soaking her body near the shoreline, whilst suddenly a needlefish jump towards her face. She was not able to dodge because it was too sudden. The fish, known with its long sharp and spear like snout, pierced through her right eyelids. She was then screaming for help. Her husband's family was then run to help her. She was quite badly injured. The wound was so deep that it even pierced through the skull and caused her to vomit blood.

She was brought to the hospital by ambulance to Kabelota Donggala hospital. Nevertheless, the wound was so bad that she eventually could not make it. She passed away in that hospital and the corpse was brought back to Balaikota Palu.

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